There is “little doubt” that the UK will be the target of a major, life-threatening cyberattack, security experts are warning.

The government-run National Cyber Security Centre (NCSC) says it is thwarting more than ten attempted cyberattacks every week. Around 70% of these attempted breaches were “undertaken by groups of computer hackers directed, sponsored or tolerated by the governments” of “nation states in some way hostile to the UK”, according to the organisation’s newly published annual review.

NCSC head Ciaran Martin predicts that the UK will at some stage face what is known as a “Category 1” cyberattack. This is defined as a national cyber emergency that causes “sustained disruption” of essential services or affects national security, “leading to severe economic or social consequences or to loss of life”.

An example of a Category 1 attack occurred in Ukraine in December 2015, when Russian hackers infiltrated and brought down the country’s power grid.

Martin added that there have already been several “very significant” incidents in the UK, reports Sky News.

He said: “I remain in little doubt we will be tested to the full, as a centre, and as a nation, by a major incident at some point in the years ahead, what we would call a Category 1 attack.

“But even if this [current situation] continues, we must be alert to the constant threat from countries who will attack critically important national networks to steal information for strategic or commercial reasons, and give themselves a starting point – ‘pre-positioning’ – for a significant attack in the future.”

Since becoming fully operational two years ago, the NCSC has dealt with a total of 1,167 incidents, ITV News says.

Minister for the Cabinet Office David Lidington, who oversees the UK’s £1.9bn national cybersecurity strategy, said: “It is easier and cheaper than ever before for those who want to do us harm to access the tools… and services they need to launch attacks.”